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  • Mark J.

So You Bought That BIG RED - NOW WHAT?

So you bought that BIG RED – Now what?

You have scoured craigslist and the facebook classifieds and you found and bought that BIG RED. After the initial excitement dies down what to do next? For me I need to check things out before I put the BIG RED to work. I typically end up following the same procedure and wanted to share it. This article has links to posts on the forum that describe some of the checks/repairs/and procedures.

Some of these items should have been done as part of an inspection before purchasing. This article assumes I am not going to do a full restoration but just get the BIG RED in good mechanical working order so I can ride it and put it to work. It also assumes that the BIG RED is complete and can run and drive.

Overall visual inspection - Grab a notebook or your phone (for the younger crowd) and do a quick walk around of the atc. Write down any missing parts and parts that you want to replace or repair.

Oil change – I always change the oil of any of the BIG REDS I purchase before I ride them or put them to work. This is just a piece of mind thing for me. I like knowing I have the correct viscosity and amount in the motor. For the 85-87 Big reds I will replace the oil filter.

Air filter – I will take the air filter element out inspect it and if ok I will clean it, oil it and replace it.

Fuel filter – The BIG REDS did not come from the factory with in line fuel filters. They did have a filter in the tank that is connected to the fuel petcock. I will take a bright flashlight and look into the gas tank to examine the condition of this filter and also if the gas tank has dirt or rust inside of it. If the filter is dirty or it I see a lot of contaminates in the tank I will drain the tank and remove the petcock and filter. The fuel filter can be cleaned with brake cleaner. Note that in many cases you will not be able to remove the filter from the petcock without breaking it. If this is the case then I will use an in line fuel filter in between the gas tank and the carburetor.

Carburetor- I will disassemble, clean, inspect, and reassemble the carburetor. For inspection I am looking for wear and correct jet sizes. I will adjust the idle mixture screw and the idle speed after all of the other procedures in this article are done.

Valve clearance – I will check and adjust the valve clearance if necessary. See attached post or the service manual for this procedure. Valve Clearance

Compression test – This will give you a good indication of the condition of the motor. Specs for compression are provided on the website. If the compression is low you may want to put a small amount of motor oil in the cylinder and retest. If the compression increases with the oil the rings may be worn. For more information on this here is a link to post that covers this procedure. Compression test.

Leak down test – if the compression test is low you can do a leak down test. This test pressurizes the cylinder and sees if it will hold the pressure. If you hear air leakage through the intake or exhaust there is a good chance that the valves are bad. If the air is leaking through the crankcase breather the cylinder/piston/piston rings may be worn. Here is a link to a post done on leakdown testing. Leakdown test

Brakes – Check brake operation. Adjust or replace brake shoes, brake cable, and brake levers if necessary. I always make sure both the front and rear brakes are operating properly before I use the BIG RED.

Drive system – First the drive chain and sprockets for the 1982 and 1983 models. I check the chain and sprockets first for excessive wear and missing teeth, rollers, and master links. If everything is in good condition I move on to adjusting the drive chain tension and then I will clean and lube the chain. For the shaft driven 1984-1987 BIG REDS I will change the differential fluid.

Starting/charging system – All the BIG REDS have electrical and manual starting capabilities. Even if I don’t want the electric start I will still put in a good battery to make sure the starting system works and make sure the alternator is charging by using a multimeter at the battery terminals.

Tires – It is a real drag (no pun intended) to get a flat tire while you are out riding. I check the tires for existing plugs, tread, and cracks. I also check the valve stem and valve core. I then check and adjust the tire pressure. Once the tire is at the correct pressure I let it sit for a day and check the pressure again. If the pressure has gone down I spray the tire with a spray bottle and soapy water to find the leak. I will plug the tire after I find the leak. Note that the plugs can fail. I have been out riding where sticks have pushed in or ripped the plug out of the tire so be aware of this risk.

Electrical switches and lights – I don’t do a lot of riding at night but I like to have the lights working. I also want to make sure that I have a switch to turn the motor off (either the kill switch on the handlebars or the ignition switch).

Wheel bearings – I’ve bought many BIG REDS that had bad wheel bearings. You can check this by getting the tires off of the ground and pulling the tire side to side and up and down to check for excessive play. Wheel bearings and seals are cheap and can improve the ride. Wheel bearings

Suspension – For the 1982-1984 models with non rebuildable front suspension I will disassemble, clean, and inspect the front forks. Many of these forks are seized up and it doesn’t take much to free them up. For the 1985-1987 models I will do a fork oil change and change the fork seals if necessary. Fork Oil Change

Exhaust – Most of the mufflers on these 30+ year old machines have holes in the mufflers due to rust. I will weld repair them mostly to quiet them down. Muffler weld repair

Fasteners – This is huge for me. Many of the BIG REDS I acquire will have loose or missing fasteners. I always check the following: motor mounts, wheel/axle nuts, racks, rear grab bar, handlebar mounts, steering stem, shifter, brake levers, and throttle assembly.

Choke – Since I live in a colder climate I make sure the choke assembly in the carburetor and the choke cable are operating properly.

Seat –If the seat is ripped I will fix them even temporarily with tape if foam is still good. Seat covers are readily available on ebay for less than 40 dollars. Exposed seat foam can deteriorate quickly. Seat cover installation

Fenders – If the fenders are cracked to where pieces will fall off I will repair the fenders by plastic welding. In certain cases I will also drill the fenders at the place where the crack stops to keep it from growing. Fender restoration

Fuel tank - Check for leaks. Some of the metal tanks on the BIG REDS are old enough that that they have rusted through and have pinhole leaks. The metal tanks can be repaired. Fuel tank repair

Again these are just some basic checks and maintenance tasks that can avoid problems caused by lack of maintenance of a previous user. Unfortunately many of these BIG REDS have a period of their life with an owner that abused and neglected the ATC. The earlier you can remedy the situation the better. There is also nothing worse than causing damage and breaking parts just because you were too excited to go out and “test” your new BIG RED.

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